What are the "levels" of broadband in relation to VOLT?

[budvesota]

If you have broadband with Virgin Media as well as a pay monthly phone contract with O2, you become eligible for VOLT. According to Virgin's website this gives you:

a broadband speed boost to the next available level of Virgin Media fibre broadband (if you don’t already have the fastest speeds you can get in your area).

Does anyone know what the "levels" actually are?

[Roger_Gooner]

Levels are M50, M125, M250, M350, M500, Gig1. There used to be M600, don't know what happened to it.

You get the next level up with Volt, so I was on M350 and was upgraded to M500.